The present invention relates generally to noise reduction, and in particular to a circuit for reconstructing the portion of an analog signal which is affected by an impulse noise.
One method currently available for suppressing impulse noise involves reducing the transmission gain or shutting off the transmission path as long as the noise is present in the desired signal. Another method involves detecting the amplitude of the desired signal in response to the leading edge of a noise impulse and retaining the detected amplitude in the presence of the impulse noise. While these methods are effective in suppressing impulse noise, the original waveform of the noise-affected part of the impulse is not compensated, resulting in unnatural sound. To overcome this problem modern digital audio systems utilize a linear interpolation technique to predict the original waveform of the noise-affected part by linear interpolation. This type of system requires complicated, expensive circuitry, not suitable for moderate cost equipments.